With all the hype about how the Industrial Internet of Things (IIoT) will change everything we do, I wondered if it could solve an age-old problem in fluid power: leakage. In an ideal world, I suppose so. In reality: not for a long time.
When I conducted research for our 70th anniversary issue a few months ago, it became obvious that fluid leaks have been a concern since the very first hydraulic system, and still are. Our very first issue, published in February 1948, described JIC standards that had recently been adopted for hydraulic fittings. The ultimate goal was to establish a fitting that would not leak—ever. Having a standard that all companies could adopt was a huge advancement for the industry. This first step was an improvement, but not a solution.
Since that time, standards have been updated and several different configurations of fittings developed to help prevent (but not eliminate) leaks. This shouldn’t be surprising: It seems unlikely that one single design of fitting would provide leak-free performance throughout all of fluid power.
One of the big challenges is that many fittings, if installed correctly, initially are leak-free. Over time, though, repeated pressure pulsations and wide variations in temperature can allow pressurized fluid to find its way out of the fitting and drip out of the fitting. It’s simple physics—a fluid at high pressure will always seek a lower pressure.
But maybe the IIoT will change that. More and more components are introduced with features that make them ready for IIoT technology, so why not fittings? Smart fittings could incorporate sensors to alert technicians that a leak may be about to occur. For example, an electrical conductivity sensor could signal when oil began to seep between the threads of the fitting and component port by detecting a change in resistance. As a result, a technician’s cell phone might receive a message to adjust a fitting, and even which fitting is the culprit.
Another scenario could be fittings with built-in load cells that signal when a fitting has loosened. An alert would be sent for a technician to tighten the fitting ever so slightly before a drop of oil ever sees the light of day. The fitting might even be able to signal when it has been tightened to the proper torque has been applied.
As with anything associated with IIoT technology, the cost of sensors must be figured into the total cost of the components. Incorporating sensors into big-ticket components may only increase their cost by 10% or so. In the case of fittings, though, incorporating sensors would increase their cost to several times that of a “dumb” version. If this type of new technology follows historical trends, we may eventually see smart fittings specified for extremely critical applications and eventually become used in more mainstream applications. This could finally spell the end of leaks, but will that happen before Hydraulics & Pneumatics celebrates its 100th anniversary?